There is established a special improvement fund in the city treasury, as provided by Section 12-6a13 of the Kansas Statutes Annotated Supplement, which may be used for the purpose of paying the cost of planning, preparing preliminary plans, studies and engineering reports preparatory to the consideration of the feasibility of, and to pay the initial cost of any improvement made under the provisions of the act until temporary notes or improvement bonds have been issued and sold. (Prior code § 1-419)